Air-pump.



H. J. HAWTHORNE, G. B. WYATT & O. P, WARNER;

AIR PUMP.

APPLICATION FILED MAR.6, 1911.

Patented Mar. 26, 1912.

Q =2 V 2a WWW w ew .a ism m HZ ings b tion on line 11-11 of Fig. 1.

UNITED STATES PATENT OFFICE.

HERBERT J. HAWTHORNE, GUY .B. WYATT, AND OTTO .P. WARNER, OF CLEVELAND,OHIO; SAID WARNER ASSIGNOR TO B. H. REYNOLDS, OF MILWAUKEE, WISCONSIN.

AIR-PUMP.

Specification of Letters Patent.

Patented Mar. 26, 1912.

Application filed March 6, 1911. Serial No. 612,659.

more especially to such as employ singleacting pistons.

The object of the invention as fulfilled by'novel changes in therelative position of diverse parts is to eifect an increased generalefiiciency.

The said invention consists of means which are hereinafter fullydescribed and particularly set forth in the claims.

The annexed drawing and the following description set forth in detailcertain means embodying our invention, the disclosed means, however,constituting but. one of va rious mechanical forms in which theprinciple ofthe invention may be applied In said annexed drawing :Figure1 is a vertical section of a machine embodying my invention, and showingdriving means in simple outline. Fig. 2 is a similar see- A hollowair-tight base A having a pipe outlet 0. supports the upright frame 13.

This latter comprises preferably an integralcylinder b interiorlyadjacent a flange b by means of which it is attached to the.

base A, as clearly shown in Fig; 1. This cylinder has its lower end 6open and somewhat above its lower extremity b is provided with aplurality of side-outlet open- A movable cylinder head C constructed asshown, is lower end 6 including the ope aings 6 within its annularrecess 0 and necessarily with the airtight connection afiorded by thepiston rings b which are located just above the openings 5 Thearrangement is such that the cylinder head 0 is normally held in closeengagement with the lower extremity 6* and in this position it closesthe openings 6 both interiorly and exteriorly as will be apparent froman inspection of Figs. 1 and 2. -The upright spring 0 exadapted toinclose the tending into the angular central] disposed depression 0serves to maintain t is normal engagement, as will be readilyunderstood.

The upper portion of the frame is made to flare outwardly in threedirections, as represented in Fig. 2, leaving one-open side whereby ahollow open compartment 1) laterally of approximate circularcross-section is provided. The open side is supplied with removablecover plate 6 for the obvious piurpose of permitting access to theinterior. An integral centrally disposed bearing 6 is further providedto accommodate the crank-shaft D, which in turn supports a driving gearE. A connecting rod F establishes an operative relation between theshaft D and a piston G1. The gear E may be driven by a pinion. H asmounted upon the driving shaft J of an electric motor, shown in outlinein Fig; 1.

A plurality of adjustably controlled. air inlets K are arranged tocommunicate directiy with the cylinder 6, and in accord ance with ourconception at points variously located intermediately of the ends of thestrokes of the piston, the precise arrangement being such that thecommunication between some of the several inlets and the cylinder,whether simultaneous or successive, is positively assured considerablyprior to the arrival of the piston at dead center, which is generallymidway of the length of the cylinder. By thus positioning the means forreplenishing the air supply in the cylinder, more remotely from the endof the returnthan from the end of the compression stroke of the piston,it becomes ossible to have the inlets disposed at di erent pointstherealong, whereby they may serve as successively operating reliefvalves for the purpose, in turn, of havingthevacuum created behind thepiston taken care, of gradually, and an equal pressure maintained throubout the return stroke of the piston. This is calculated to insure thatuniform load which is so prominent a requisite to general efficiency. I

Our air pump in the nature of a selfcontained structure, is calculatedto operate in the following manner: The reciprocation of the piston Gthrough the medium of the operating mechanism first alternatelycompresses the air in the cylinder and drives it out through theopenings 6 against the action of the cylinder head, as will be manifest.Durin this alternate up and down movement 0 the cylinder head C, an aircushionin efi'ect is established between it and the lnclosed portion ofthe cylinder, whereby a substantially noiseless vvalve structure isattained. The hollow air-tight base meanwhile constitutes an airreceiver from which the air under compression may be more uniformlywithdrawn by reason of being partially independent of the intermittentdischarges, from the cylinder. This should carry quite an appreciablevalue where, forexample, it is intended to inflate the rubber tires onautomobiles. During the return stroke of the piston, the properlyadjusted inlet valves will very adually overcome the vacuum so that atthe end of the stroke none at all remains, and hence the jolting atpresent resulting from the sudden inrush at the end of each alternatestroke is positiyely precluded.

Having fully described our invention, what we claim and desire to secureby Letters Patent is 1. An air pump comprising a cylinder having one endopen and provided adjacent thereto with a'lateral opening, a pistonwithin said cylinder, operating mechanism connected with said piston,and a movable cylprovided with an annular recess adapted to lnolose saidend and opening.

2. A11 air pump com rising a cylinder having near one end a p uralityofcircumferentially disposed openings, a piston within said cylinder,operating mechanism connected with said piston, and a movablecylinder-head adapted toboth interiorly and exteriorly close saidopenings.

3. An air pump comprising a frame having a-hollow member, a cylinderhaving an open end extending into. said member, and provided with an.inlet and a side outlet, the latter communicating with said hollowmember, a movable cylinder-head provided with a recess adaptedtosuccessively close said cylinder end and side outlet, an operatshaftpromoting into said frame, a pinion upon said shaft, a driving gearengaging said pinion, a crank-shaftconnected with said gear, aconnecting rod secured to said crank-shaft, and a piston pivotallyconnected with said rod, said cylinder being provided with an air inletmore remotely lo cated from the end of the return than from the end ofthe compression stroke of said piston, and-an air outlet within saidchamber located near said open end, and adapted to be closed by saidcylinder head.

Signed by us, this 28th day of February,

HERBERT J. HAWTHORNE. GUY B. WYATT. OTTO P. WARNER. Attested by-- GnonsnW. ELLSASSER, C R'r B. MUELLER.

